Hey guys, so I just got done replacing the head gasket and head (Clearwater cylinder heads) on my 1998 xj, 137k miles, along with it I replaced a ton of other things like the water pump, thermostat, and all new exhaust. I started it for the first time tonight and it sounded good, but there was a fast leak from where the engine block Mates with the transmission, from what I have read, it could be a freeze plug on the engine block? Or the heater control valve? S

 

You have no heater control valve on a 98. Coolant coming out between the engine and trans?

 

Did u seal up the freeze plug on the back of the cylinder head?

 

That's unfortunate...it sounds like it is either the block or the cylinder head freeze plug. If it didn't leak before with the old head, I'm going to guess that's where the leak is, and you'll have to undo your hard work and ruin the new gasket to fix it.

If you were desperate, you could smear some JB weld around it by feel...maybe....but I wouldn't recommend it!

 

It was a new head and I didn't touch the freeze plug aha was I supposed to?

 

It should have been sealed by the remanufacturer. I don't know, u gotta check and verify if that's where it leaks. Maybe it's somewhere else

 

Yeah well if it's just one of the plugs on the side of the block that would be easy enough, or one of the two plugs on the rear of the head, I'd just have to pull the tranny

 

So after going back out today i ran it some more and theres no more leak, i topped off the coolant level and still i dont see any leaks, so for now ill keep a close eye on it

 

If it does turn out to be the rear freeze plugs on the block, Melling sells a nice brass freeze plug kit for the 4.0L. The quality is much better than the cheap plugs from Autozone. It's around $16-19.

Here it is from Golen (cheaper than eBay): https://www.golenengineservice.com/products/jeep-brass-freeze-plug-kit

I also use this Permatex Aviation Sealer to seal it (I coat the entire plug with it):

http://www.napaonline.com/Catalog/Ca...210_0006382656

 

Got it! Thanks for the info

 

 

so are those two freeze plugs covered up by the bell housing?

 

Ones a freeze plug the others oil.

 

Ah okay gotcha, and is the one Greece plug covered by the bell housing?

 

Yes. Both of those are behind the bell housing and flex plate.